The sticky secretions in the lungs of patients with chest disease clog the airways, causing pneumonia and often death. How the body controls the consistency of airway secretions is not known. We have developed two new methods to allow us to study the control of the consistency of the secretions. First, we studied salt pumps in the airway lining because, in other organs which produce secretions, the water movement is regulated by salt pumps. We found salt pumps in the dog airway lining which could regulate the wateriness of secretions. They were located on the same side of the airway lining as the nerves and blood, and were stimulated by drugs which mimic the effect of nervous action. Secondly, we studied the secretion from individual, tiny glands in the airway lining of the dog. We coated the airway lining with fine, inert, metal dust (tantalum), photographed, and videotaped the coated airway surface through a microscope. We stimulated electrically the nerves to the airway; small elevations, "hillocks" appeared in the coating. We found that each "hillock" was over an opening leading to a gland. using the "hillocks" as markers, we found that the glands were controlled by branches of cholinergic nerves and that the rate of secretion could be increased or decreased by drugs. We have collected secretions from individual glands in tiny glass tubes and analyzed the salt and protein content. We will use these methods to discover how stimulation of nerves and reflexes influence the consistency of the airway secretions and how they may be altered in diseases like cystic fibrosis.